Dichio, who is on the transfer list at the Hawthorns struck three times in the opening 19 minutes as Albion secured only their second win in 17 games.
The former Sunderland striker has now scored six goals this season with all of them coming in Albion's last four home games.
His quick fire treble ensured there was never going to be any chance of Bradford pulling off an upset.
The defeat only added to Bradford's dismal record on their travels this season.
They have lost 10 of their last 11 away games and all they have to focus on now is their first division survival fight.
They never seriously tested the Albion goalkeeper Russell Hoult until substitute Mark Danks grabbed a consolation goal in the 78th minute.
Danks, who was sent-on after 55 minutes in place of Juanjo, nodded the ball into an empty net from two yards when he latched on to a rebound after Claus JorgensonÂ’s 30-yard drive had crashed off the bar.
But Bradford's hopes of pulling of a shock were effectively dashed after just four minutes when Dichio opened his account.
His first two goals came from powerful close-range headers, while his third was a neat finish with a low drive.
Dichio opened his account with a fourth minute header from a right-wing cross by Adam Chambers before he doubled advantaged by heading home a left-wing cross from Jason Koumas seven minutes later.
Bradford did not know what had hit them and they were still reeling when Dichio grabbed his third in the 19th minute.
He owed that goal to his strike partner Jason Roberts who raced clear from the halfway line and held off challenges from Mark Bower and Robert Molenaar before feeding a neat pass to Dichio who rolled his shot beyond the right hand of goalkeeper Aidan Davison.
Albion should have added to their advantage in the second-half, but midfielder Andy Johnson and substitute Scott Dobie both wasted clear openings from close range before Danks gave Bradford some reward for their efforts.